Answer:
They can occur anywhere from thousands to billions of years.
The correct answer here is C - out of the developments listed, the most
recent development in the use of vaccines was the approval from the
government of a vaccine that can be used against Hepatitis B. This
happened relatively recently, in 1981.
1. Simple Diffusion is a passive transport in which particles pass through the plasma membrane surrounding a cell. Diffusion is the random movement of particles with the net direction of the particles being from an area of higher concentration to an area of lower concentration.
Answer: hundreds of millions of years ago